1. Field of the Invention
The present invention relates to an optical disk driving unit and, more particularly, to a pickup controller for controlling a pickup of the optical disk driving unit. A laser driver is provided in the pickup.
2. Description of the Related Art
A pickup for irradiating a laser beam to an optical disk includes a laser driver for supplying a drive current to a laser unit. Due to an increase in recording capacity of an optical disk, recent technology has advanced to develop multi-intensity recording lasers, as well as a more highly precise architecture for adjusting the pulse width of recording lasers. An optical disk driving unit includes a pickup, and a printed circuit board provided with circuits such as controllers. A technique for mounting a laser driver inside of the pickup, and mounting a controller on the circuit board has been proposed. Since the pickup is able to repeatedly shift back and forth within the inner and the outer peripheries of the dish, the pickup is connected to the printed circuit board by a flexible-cable.
Functions of the pickup have increased because of increases in recording capacity and recording speed, and diversification of the recording medium. A pickup having functions such as using a plurality of lasers in accordance with the recording medium, forcibly turning off the drive current, and increasing the gain of the drive current for high-speed recording, has been developed.
In the foregoing related art, securing a plurality of signal lines for controlling the functions in the pickup is necessary because of the increases in the functions of the pickup. That is, a signal line for selecting the lasers in accordance with the recording medium, a signal line for forcibly turning off the drive current, and a signal line for increasing the gain of the drive current for high-speed recording must be provided in the flexible cable. As a result, since the number of signal lines increases, there is an increase in the implementation area and a decrease in reliability of connectors connected to the flexible cable.